Handpiece for dental engines.



a 4 A. E. KELTIE. Y

HANDPIEGE FOR DENTAL ENGINES. APPLIGATIGHFILED 1350.4, 1911.

1,056,34;L Patented rm. 18, 1913.

Snucnfoz once ALEXANDER R. KELTIE, 0F BOSTON, MASSACHU SETTS.

HANDPIECE FOR DENTAL ENGINES.

Specification of Letters Patent.

Patented Mar. 18,1913.

Application filed December 4, 1911. Serial No. 663,846;

T 0' all. whom, it may concern:

Be it known that I, ALEXANDER R. KEL- TIE, a citizen of the United States, and resident of Boston, in the county of Suffolk and State of Massacln1setts,.have invented certain new and useful Improvements in Handpieces for Dental Engines, of which the following is a specification.-

The invention relates to .improvements in handpieces for dental engines, and more particularly to the angle attachment disclosed in Patent No. 522,291, granted July 3, 1891, to C. II. Davis.

It has for its object. to simplify and cheapen the construction without detracting from the etliciency of the device.

The invention consists in the novel construction, combination and arrangement of parts, hereinafter rle'scribechpointed out in the appended claim, and illustrated in the accompanying drawings.

In the drawings, in which similar refercharacters designate corresponding parts, Figure 1 is a side elevation, partly in section and broken away. in parts, of, an attachment embodying the invention.- Fig. 2' is a sectional view of theangle-head and end of the casing, the operating parts being removed. Fig. 3 shows end" and side views. of the angle-head. Fig. i is a sectional View on the line 41 of Fig.1. Fig. 5 shows edge and planviews of the screw-ring for holding the anglehead'and casing in rotatable connection. Fig. 6 is a detail View of the bur-holder and driving gear. Fig. 7 shows the upper end of the bur. Fig. 8 is'a detail view of one of the gear-wheels.

Inone end of the cylindrical holder 1 is secured the tubular casing 2 by the screw 3 passing through the holder and easing. In the tubular casing is theshaft- 4 journaled in the bearing sleeve 5 interposed between the shaft and the casing. The inner end of the shaft 1 extends into the holder 1 and is flattened, as at G, to form the driving connection with the flexible shaft inserted in the end of the holder. On the outer end of the shaft .1 is the head 7 rotatable in the outer end of the tubular casing 2 and abutting the outer end of the bearin -sleeve 5. I he latter by abutting the head 4' prevents longitudinal movement of the shaft within the tubular casing. On the crown of the head 7 is the bevel-gear 8.

On the outer end ofthe tubular casing 2 is the annular neck 9 bent at an angle to the main direction of casing. At the edge of the annular neck is the flange 10 (Fig. 2). In the angular bend betweenthe main casing 2 and the annular neck 9 is the partition 11 extending across the interior of the casing. In one side of this partition is an opening 12 through which an edge of the bevel-gear 8 projects into the compartment formed by the annular neck;9. From the partition ll'projects the stud 13 concentrically into the chamber formed by the annular neck. On the studp13 is journaled the double gear-wheel 14 (Fig. 8) having on one face the bevel-gear 15 meshing through the opening 12 in the partition 11 with the bevel-gear 8 on the shaft -l, and on the other face is the bevel'gear. 16 extending beyond the annular neck 9. The back edge of the bevel-gear 16 bears on the end ofthc annular neck 9, which prevents a crowding together of the gears 15 and 8.'

-'Rotatably adjustable on the outer end of the tubular casing 2 is the angular head 17. In one arm 18 of this head is screwthreadcd the retaining ring 19 (Fig. 5) journaled on the annular neck 9 inside of the flange 10. This ring is cut, as at 20, so that it can be sprung over the annular neck back of the flange preliminary to being screwed into the arm 18. The ring 19 not only serves to hold the angular head in place on the outer end of the shaft 1, but by turning on the neck 9 also forms a bearing whereby the angular head can be rotatably adjusted on the tubular casing.

- Theangular head 17 is hold in its adjust ment on the tubular casing 2 by the spring pawl 21. The latter lies in the longitudinal groove 22 in .the casing with its inner end extending under the cylii'nh'ical holder 1 and thereby held in place. The free end of the pawl, when depressed, engages the teeth 23 on the end of the arm 18 of the angular head. The pawl toward its free end, as at 24, is thickened so as to project above the surface of the tubular casing. Slidable on the tubular casing is the ring 25. which when moved outwardly engages the thickened part. of the pawl and holds the latter in engagement with the teeth 23. With the pawl 21 in engagement with the tectlr23 and the ring pressed outwardly on the thickened part 24 of the pawl, the angular head is locked in the position to which it is adjusted on the tubular casing.

Into the outer end of the arm 26 of the is screwed the cap 27.

angular ournah i sleeve with it ing into the top of the arm. @n the inner end of the sleeve is the collar 29 journaled in the bearin 3 (Fig. 2) in the upper part or the arm This collar not only forms a rotatable for the inner end of'the sleeve, but'also serves to take up the inward hrust cit-the sleeve. in the extreme inner end-ofthe sleeve is .the flattened part 81, the purpose or whichwill he explained furor on. Fixed on the sleeve 28 just inside or the cap is the bevel-gear 32 meshing with bevel-gear 16 of the double gear- .vheel. i l. The back of the bevel-gear 32 the cap 2? forms astop to ent the outward movement of the sleev'e through the ca i hanlr sleeve and 3d 7 the sleeve turned th the end 'ne grinding bur 33 fits the inner end is notched, as at the ilattened part 31 of 28 so that when the sleeve is e bur will be rotated with it. At if shank is the annular groove with which engages the latch 36. The latter is slidable in recess (Fig. 3) in the angular he 'l 17, the pin 38 jectin Ir lip 39 so that it can be readily opened "3 the sleeve while the latter is rotated. .nl operation, the bur having been sein the sleeve 28, the angular head 17 having been adjusted on the tubular casing 2 to the angle required by the work, and the attachment coni'iected with the usual flexihle sha'fting; on the application of power the shaft 4 is rotated and through the meshing bevel-gears 8 and the double gear wheel 1% is driven. Through the meshing hevelgears 1t and 32 motion is transmitted s outer e d-in this cap is the s inner end extender will be held in place withoaaaai Iclaiin and desire to secure by Letters Patcut is: a y

In an. angle attachment for dental engines,

a tubular casing, an annular neck on the endof the casing bentat an'ari'gle to the longitudinal direction of the casing, a partition in the casing at the bendbetween the casing and neck, said partition having an opening in one side, a shaft journaled in the casing, a bevel-gear on the shaft projecting through the opening in the partition, a stud on the partition projecting concentrically into the annular neck, a Wheel journaled on the stud having a bevel-gear on one end meshing with the bevel-gear projecting through the partition and said wheel having a bevel-gear on its other end" projecting beyond the an nular neck with the back of the last mentioned bevel-gear riding on the end of the annular neck, an angular head having its inner arm journaled on the annular neck and its outer arm provided With a bearing in its inner end, a sleeve journaled in the outer arm of the angular head having a flat- ALEXANDER R. KELTIE.

Witnesses: v i

Orls ATKINSON,

W. C. SCHWARTZ. 

